A oobpobation



March 28, 1933.

B. JOHNSEN PAPER MANUFAGTURE Filed sept. 1a, 19:50

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BY mv'ron mama Mmes. 193s UNITED STATES P'ATENT oFFicE mamita Jcimsnn. or anni. rnmrmvama. ancianos ro annimmt. Parmi. coilrm. or snm. rmmmvama, a oonronarion or rmsrnvmra raras monarcas appumm ma ummm-ia, im. anni no. massi.

This invention relates topaper manufacture. In the manufacture of most papers used for and printing, it is necessary to add to the paper pulp so-called sizing materiale for the purpose of covering the surface of the fibers with' an adhesive material there'- by sealing up the natural pores of the libera and eervin 4as a bindin material between the indivi ual libere. e sini moet common] used is rosin, whic is added to the so-call beating engines either in the forin of sodium resinate or 'asa colloid solution of free rosn or as a combination of aodium resnate and free resin, the latter bein'g the customa practice. In order to bring abcurh reaction betweench the roiln an e rs, 1 is n to ange e acidity of the solution bg ding an ac id or salt; and aluminum sulp ate has been found to be thempst suitable salt for this reaction and is therefore most commonly' used. Fol lowing this reactionJ the apexpulp is a'cid in character and this aci ty d e ds uponA the amount of aluminum sulp te added which again is governed by the local manu facturing conditions of the individual p aper During the formation of the a r sheet on the Fourdrinier wire, most of acid water is removed from the sheet but sujcient acid water is left to given' distinct acidity .to 'the nal dried tpaper sheet. It has beenfound that the aci ity of the paper afecte its durability adversely and that a minimum acidity should be maintained in the apar shect t0 insure greater permanence of the paper.

The ailinity between the bers and the resin particles is not suicient to retain in the sheet the totalrosin added to the paper pulp, a. eatpprtion being removed during the rapi draining of the water on the paper machine .wire an while some of the .unattached resin particles may be held by tbesheet particularlyonfthe upper aide, practically all succlzartielee are removed iro'm the lowerside ed the wire side) due. to the suction of the suction boxes. and the suction roll.

creates a disturbance ofthe lower surface' of the sheet and a dierence between the, two

waidesofthepaper. Wblothieeanbecom.

material starch er starch pr This separates from the stoc pulled out of the wet'stoclc orslieet as the trolled by surface sizing b assi' the dried or partl dried sheet throdrgb a bxdi contain 1 a so ution of glue 'or starch or a mixture o f th or other material, such additional treatment is costly and moet aper se machines are not equipped for it ande installation of the necessary equipment would add materially'to the production cost.

For the purpose of improvingthe surfaces ooi the padler sheet, it is also common pracno tice to a to the aper nlp in the beater nets, ut these have ve little ainitglto the libre and with the hig dilution of e starch as it enters on the paper machine wire and the rapid drainage necese5 I sary on thewire, most of the starch material is removed and only a small is re aannames n 11g I 'have developed a` method .whereby starch or other sizing material may be incorporated 10 in the sheet in greater concentration and with better surface eect, simultaneously reducing the acidity of the sheet and improving its -quality in respect to durability or perma- .2isaverticalseetional viewoia detail. s0 Re erring to the drawing a Fourdrinier machine of standard construction is indie d at 2, said machine ccmpri's'- ing a' well-known Fourdrinier screen or wire 3 which is caused to travel in the usual wa a6 over a series of rollers including-suction ro l 4 and table rollers 5. The screen B also passes over vacuum' boxes 6 of standard construcpapemna tion. vAs is well-understood in the'art the perstocliorpulpetreamdowsfroma aad bnxv'fcnto thescreen orwire B andiscarried along bythe latter. When flowing onto the .w're the par stock'has a concentration' ci, approrima y-.ne half of one cent liber and material to 99.6 Icent crater; A s ntial portion of e .water by gravity, 4iwliuz forations o the screen or ei" portion of the water is `through the wire 8. Ano' wire passes over the suction boxes 6 and suction roll 4, so that the sheet finally leaves the wire with about twenty percent solids (fiber and sizin material) and eighty percentI water. The sheet thence is carred by a strip 8 of felt or similar material between the customa rassure rollers, such as are indicated et 9. ence the sheet passes to drying cylinders (not shown) of the usual t In carryin out my invention add a starch solution or ot er suitable material to the sheet or .paper stock while the latter is on the Fourdrmier wire 3. Said material is added in any convenient way, such, for example as by means of a box 10 suitably secured to the frame of the paper machine and havin anV overflow assage 11 from which exten s a li 12. Slaid box, overflow passage, and lip extend across the full width of the ma chine, and the solution to Vbe added to the stock on the wire 8 may be flowed continuously into compartment 13 of the box 10 in any desired manner. -A partition 14 extenti-` downwardly hut terminating above the budtom of the box divides the box into cornpartments18,15. The overow -communicates with com artment as shown.

The 'partition 14 ena es a unif il'ow of solution to be obtained through the overow passage 11 and eliminates the eiect of undesirable currents which might be caused by the entrance of the solution into the box 10.

A smooth and continuous dow of solution thus takes place over the lip 12 tothe stock on the wire 8.

The sizing material is carried'along the wire 8 with the slpaper sheet or stock and .is

drawn into said eet -the action of gravity supplemented thdyaction of the suction boxes 6 and su on roll 4. Said sizing ma terial thus dillaces the acid solution originelly in the eet, replacing the d' acid material and'decreasng the acity of the paper while at the same time increasing the amount of starch therein. When the wet sheet passes throligh the pressure rollers 9, a. further quantity of water is removed from the by lrssure and some of the starch contained in water is forced by said pressure to both surfaces of the sheet. When thas sheet thence passes to the drying c linders the heat of the latter causes the to forma film on the surfaces, imlrovi'ng the writing and printing qualit!! of e pa r. Itis to be noted t at through my invention an im rovement not onl also o the entire body ofY the pape r is accomplished. This is in marked distinction to the customary surface wherein merely a 'driiu film is formed on the surface and can b`e re moved by erasure, leav' a new 'surface of inferior sizing uality. y invention brin about not mere y a surface treatment, but a treatment of the entire aper y.

The position of the x on the Foursaid solutionto the stock.

.thelatter -ona F said qstock of the surface but drinier machine ma be varied according to the point at which the sizing solution is to be added to the stock on the wire 8. Preferably the sizin solution is added to the stock at a oint w ere a substantial amount of water as been removed. In the accompanying drawin the box 10 is 4shown in such position on the ourdrinier machine as to add the sizing solution to the stock where the latter consists of approximately ve ercent ber and ninety-live 'percent water, ut it will be apparent that the invention does not depend upon' any particular point of a Sai int of a plication ma be varied as desired. If t e solution is a ded at a point where a small quantity of water has been removed the solution should of course be r than when added ata point where more water has been removed, assuming the same. amount of sizing material to be desired in the sheet.

While I have s cally mentioned starch, it will be eviden that the invention is applicable to any starch products or other materials. The 'inventiqn may in fact be em p loyed for impregnatin the paper with any similar -non-acid material uantity of 'acid matter in the pa r and t ereby reducin the acidity of the ttor.

The terms an expressions which I have employed are used as terms of description and not of. limitation, and I have no intention, in the use of suchterms and e excluding an equivalents of the features shown and escri or thereof, that various modifications are for displacing a xpons, of

plication of recognize possible` vntliin the sco' of the invention claimed.

1. 'That improvement 'in'.the art manufacture which com a'd material to paper stock f elw uringthe er wire.

-2. That improvement in the art of manufacture which comp material to a Fou .d PPP perstock while the la er wire and causing the'body of to be impregnated with said ma- That improvement in the art ofi paper manufacture which comprises ad sizing material -to whilethe 'ch com 'rises adding stare to paperstock while'theplatter on a er .wiieg'causing said starch to' tributed through'the body of the ilpon the lower as well 'as the upper ereof anda l' heattos'aid starch. s. a mshoapgflaimmmg g'" as acidity of paper 'stock w cli L com rises adding nonacid material toltlie'stock gvlile the latter is on duavel o5 l ison'.

bedis-.

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tter'is n a, Fourdrinier wire and sub'ecting said mnterial to suction to cause sai material to displace acid matter from within the body of said stock.

5 6. That improvement in the art of paper manufacture which comprises treating the paper stock during its travel on n Fourdriner wire with szin material and causingA said material tq disp ace acid matter from with- 10 in the body of said stock.

In testimony whereof, I have signed my name to this specification this 27th day of August 1930. l BJARNE JOHNSEN, 

